As the typical unconventional superconducting state, we focus on two-dimensional \(p_x\) - and chiral \(p_x+{\rm i}p_y\) -wave states,
where the latter is suggested in Sr\(_2\) RuO\(_4\)  superconductor.
[1]}, [2]}, [3]}, [4]}, [5]}
For simplicity, we assume a single cylindrical Fermi surface.
To determine the frequency and spatial dependences of the order parameter,
we use the quasi-classical Green's function introduced by Schopohl et al. to study the vortex problem.
[6]}, [7]}, [8]}, [9]}
We adapt this scheme to the boundary problem and apply it to both the cases of surface and the domain wall
by extending our previous formulation
[10]}
to include the odd-frequency order parameter.
